The present invention pertains to portable hoists and cranes, and more particularly pertains to such a combination portable hoist, crane, and automobile towing mechanism that (1) includes a support for use as a conventional hoist, (2) when mounted on a modified vehicle bumper, is used as a portable crane, and (3) when mounted on a modified vehicle bumper, is used as an automobile towing mechanism.
Portable hoists are well known in the field of auto shop mechanics for use in removing, installing, and transporting automobile engines and transmissions within the workshop area. Such a portable hoist generally comprises a pair of fixed or extendable legs or feet, generally formed in the shape of a V, with a vertical shaft or mast affixed to the legs at the juncture of the V. A raisable boom is pivotally attached at or near the top of the mast in a manner that the boom may pivot to raise and lower the end of the boom. Generally a hydraulic cylinder is connected to the vertical mast and the boom to provide the force to raise and lower the boom. The end of the boom generally includes a chain or cable having a hook on the end thereof for hooking onto the object to be raised and/or moved. With numerous variations, this type portable hoist is well known and used by automobile mechanics for removing, transporting, and installing engines, transmissions, etc.
A device similar to the vertical mast and boom aspect of the portable hoist has also been used with vehicles to define a small mobile crane for loading and unloading objects and materials to and from a truck bed. In such a configuration, the vertical mast is mounted to either the truck bed or a modified truck bumper, and generally pivots about its vertical axis (the mast) in a manner to swing to and from the truck bed to load and unload objects and materials. U.S. Pat. No. 4,508,233 describes such a combination portable hoist and lifting crane mountable on a pylon plate that is permanently mounted to the bed of a truck.